• Economic and Environmental Geology
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• v.56 no.4
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• pp.421-433
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• 2023

The final disposal of spent nuclear fuel(SNF) from nuclear power plants takes place in a deep geological repository. The metal canister encasing the SNF is made of cast iron and copper, and is engineered to effectively isolate radioactive isotopes for a long period of time. The SNF is further shielded by a multi-barrier disposal system comprising both engineering and natural barriers. The deep disposal environment gradually changes to an anaerobic reducing environment. In this environment, sulfide is one of the most probable substances to induce corrosion of copper canister. Stress-corrosion cracking(SCC) triggered by sulfide can carry substantial implications for the integrity of the copper canister, potentially posing a significant threat to the long-term safety of the deep disposal repository. Sulfate can exist in various forms within the deep disposal environment or be introduced from the geosphere. Sulfate has the potential to be transformed into sulfide by sulfate-reducing bacteria(SRB), and this converted sulfide can contribute to the corrosion of the copper canister. Bentonite, which is considered as a potential material for buffering and backfilling, contains oxidized sulfate minerals such as gypsum(CaSO4). If there is sufficient space for microorganisms to thrive in the deep disposal environment and if electron donors such as organic carbon are adequately supplied, sulfate can be converted to sulfide through microbial activity. However, the majority of the sulfides generated in the deep disposal system or introduced from the geosphere will be intercepted by the buffer, with only a small amount reaching the metal canister. Pyrite, one of the potential sulfide minerals present in the deep disposal environment, can generate sulfates during the dissolution process, thereby contributing to the corrosion of the copper canister. However, the quantity of oxidation byproducts from pyrite is anticipated to be minimal due to its extremely low solubility. Moreover, the migration of these oxidized byproducts to the metal canister will be restricted by the low hydraulic conductivity of saturated bentonite. We have comprehensively analyzed and summarized key research cases related to the presence of sulfates, reduction processes, and the formation and behavior characteristics of sulfides and pyrite in the deep disposal environment. Our objective was to gain an understanding of the impact of sulfates and sulfides on the long-term safety of high-level radioactive waste disposal repository.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.60-65
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• 2000

Biosorptions of Cr and Pb were evaluated for 23 species of marine algae collected from a Korean coast. Among a variety of species for biosorbent potential, Sargassum species showed higher uptake capacity for Cr and Pb. An adsorption equilibrium was reached in about 1 hr for Cr and 30 min for Pb. The maximum uptake capacity was136.0 mg Cr/g biomass and 232.5 mg Pb/g biomass, respectively. In Pb biosorption in the column packed with Sargassum tbunbertii, 300 and 200 bed Tolumes at the concentration of 50 mg/L in feed solution were processed at the column residence time of 5 and 10 min before the column breakthrough point occurred. The elutions with 0.1 M HCl solution were more than $95{\%}$. The high efficiency of continous biesorntion and elution (3 cycles) indicated that Sargassum thunbergii was an effective biosorbent for Pb recovery.

• Journal of Korean Home Economics Education Association
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• v.27 no.4
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• pp.1-18
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• 2015

The purpose of this study was to conduct a course entitled 'Teaching practice' applying Problem Based Learning(hereafter PBL) for perspective Home Economics teachers to explore the applicability of PBL to the course. A course entitled 'Teaching practice' was carried out for 17 undergraduate students from the 2nd of March till 11th of June in 2014. Pre- and post-tests to measure teacher disposition were performed to investigate the effectiveness of the course applying PBL. Three questions for PBL were developed, were determined after obtaining verification of the questions from 5 experts, and were used for the course entitled 'Teaching practice'; Developing teaching-learning plan, establishing plan for homeroom class management, and designing assessment of Technology & Home Economics. The processes of PBL include defining the problem, planning problem solutions, reassessing the problem, identifying possible solutions, and performance presentation. Procedures for solving one problem of PBL took 4 weeks and teacher disposition assessment for effectiveness of PBL was carried out for pre- and post tests. The reflection journal showed that even though it was their first experience of PBL, instructor's feedback, group activities, and individual activities were helpful for solving the problems of PBL. The result of dependent t-test for paired samples revealed significant differences between the pre- and post tests, which means that there was effectiveness of the course applying to PBL on teacher disposition of prospective Home Economics teachers.

• Journal of the Korea Society of Computer and Information
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• v.18 no.9
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• pp.165-175
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• 2013

Though the number of food franchises has been increased these days, there has not been less success for food franchise than failure. One of the several failures is the distrust between franchisor and franchisee factors because the franchisee thought its franchisor does not make its accounts and operations transparent. In order to resolve it, the large business food franchise has used the ERP system, however, small business franchise has run a very simple information system, which is linked to POS system and consists of simple functions to insert or inquire the result of data on sales and order etc to identify the status of both franchisor and franchisee because of financial difficulties and manpower shortage. Thus, small business franchise needs the cost management between them with low cost for efficient business administration. In this study, we suggest the data reference model (DRM) which covers the cost management system and is able to be linked to any POS system. The DRM is a framework whose primary purpose is to enable information linking and reuse across the any POS-based information systems via the classification, structure, model, exchange and management of data.

• Journal of the Korea Society for Simulation
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• v.22 no.4
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• pp.11-19
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• 2013

The Korean naval weapon systems, combat experiments establish the concept of Battle operations, and create the future of the new weapons system. Doctrine development and training as well as ranging from experiments for evaluate the performance of mission operations for combat experiments are used. The battle lab is effectively support tool for the Korean Naval battle experiments. The battle lab is through a dedicated testing facility and to build efficient and effective simulation-based acquisition supporting environment. In this paper, the ship / submarines C2 operations virtual simulator was developed to support the concept of Battle operations of naval combat experiments in training and tactical development. The ship C2 operations virtual simulator makes the anti-ship and anti-aircraft the engagement scenario for performed experiments using the SADM. The submarines C2 operations virtual simulator makes the anti-submarine engagement scenario for performed experiments using EAS. EAS System was created before reuse. EAS system by modifying the additional interfaces HLA-RTI has been reused. Reflected in the tactics and training after analysis of the results through the battle experiment. Also increase training fidelity through operator involvement. The anti-ship and anti-aircraft system architecture (SADM) and anti-submarine system architecture (EAS) requires unique design of system framework since two separate architectures should be integrated into a system. An C2 virtual linked architecture was used to integrate different system architecture. A C2 virtual linked software framework, designed that have integrated protocol for battle experimental linkage and battlefield visualization environment.

• Korean Journal of Environment and Ecology
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• v.11 no.1
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• pp.46-60
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• 1997

The purposes of this research are to select the appropriate kinds of landscape woody plants for afforestation artificial ground and to find out the way of developing planting-tree area of artificial ground through test planting and case study. The summary of the research is as follows; As a result of observing the state of trees' growth, trees on artificial grounds grow as well as, or even better than those on natural grounds. The kinds of trees which represent better growth states on artificial soil of rooftop test area are Thuja occidentalis, Prunus armericana var. ausu, Acer palmatum, Viburnum sargentii for. sterile, Buxus microphylla var. koreana, etc. In addition, soils than on natural soils. As a result of investigating the tree's growth state according to soil beds of artificial soils, shrubs don't represent distinct differences. They show that shrubs can be planted on 30cm soil bed. The rest of trees no differences according to the variation of soil beds, and they are in normal condition or have slight damage. This means that though arbor planting area of artificial ground is made 45~60cm, it is possible for trees to grow on it. In consequence of analyzing the cases on areas of landscaping artificial grounds, as the appropriate kinds of trees for afforestation artificial ground, Diospyros kaki, Hibiscus syriacus, Syringa dilatata, Magnolia kobus, Acer ginnala and cornus alba are selected in Capital region, and Nandina domestica, Taxus cuspidata, Ilex crenata, Viburnum awabuki, Aucuba japonica and Euonymus japonica are selected in southern region. In addition, Juniperus chinensis, Zelkova serrata, Juniperus chinensis var. kaizuka, etc. are selected regardless of regional character. In accordance with the state of soil it shows great difference, namely, fertilization once or more a year and irrigation for drought is advantageous to tree's growth. This research represents that it is necessary that standards related to landscaping artificial grounds are subdivided. In addition to it, the plan for revising related to regulation is drawn up.

• Journal of the Korean Institute of Gas
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• v.21 no.4
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• pp.47-61
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• 2017

The preconditions of the usefulness of an operator safety training model in large plants are the versatility and accuracy of operational procedures, obtained by detailed analysis of the various types of risks associated with the operation, and the systematic representation of knowledge. In this study, we consider the artificial intelligence planning method for the generation of operation procedures; classify them into general actions, actions and technical terms of the operator; and take into account the sharing and reuse of knowledge, defining a knowledge expression ontology. In order to expand and extend the general operations of the operation, we apply a Hierarchical Task Network (HTN). Actual boiler plant case studies are classified according to operating conditions, states and operating objectives between the units, and general emergency shutdown procedures are created to confirm the applicability of the proposed method. These results based on systematic knowledge representation can be easily applied to general plant operation procedures and operator safety training scenarios and will be used for automatic generation of safety training scenarios.

• Journal of Wetlands Research
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• v.17 no.1
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• pp.38-44
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• 2015

In Korea, most rainfall events occur during summer which then leads to an increasing concern regarding high influx of non-point source pollutants since the pollutant loadings from these non-point sources are very significant. In particular, the first flush of roof-harvested rainfall is said to contain the most highest concentration of nutrients and heavy metals. Accordingly, it is important to develope the possible water quality management options in treating the contaminants and considering reclaimed water reuse. The rain garden could be one of suitable alternatives in addressing this issue. In this study, the development of an effective adsorption media and its application to a lab-scale rain garden was tested to evaluate the removal rate of various nutrient and organic matter (TN, TP, CODcr), and heavy metals (Cu, Cd, Pb). Results showed that carbonized peatmoss produced at higher temperature have better adsorption capacity as compared to the one produced at a lower temperature. When the carbonized peatmoss was applied as rain garden media, the highest removal of TN, TP, and CODcr was observed compared to no carbonized peatmoss applied rain garden. Therefore, this study showed that the carbonized peatmoss would be effectively applied to the rain garden for removing nutrients and heavy metals from roof-harvested rainwater.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.1
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• pp.40-50
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• 2016

A BIM, which is being applied actively to the construction and civil construction industries, is a technology that can maximize efficiency of various sectors from initial planning and design, construction, and maintenance, to demolition; however, it is in the introductory phase in the field of domestic landscaping. In order to introduce and promote BIM in the field of landscape design, this study developed a prototype of a library and template and analyzed the performance of trial application. For the development of a prototype, annotations and types were analyzed from floor plans of existing small parks, and components of landscape template were deduced. Based on this, play facilities, pergola, and benches were madeintofamily and templates, making automatic design possible. In addition, annotations and tags that are often used in landscape design were made, and a 3D view was materialized through visibility/graphic reassignment. As for tables and quantities, boundary stone table, mounding table, summary sheet of quantities, table of contents, and summary sheet of packaging quantities were grouped and connected with floor plans; regarding landscaping trees, classification criteria and name of trees that are suitable for domestic situations were applied. A landscape template was created to enable the library file format(rfa) that can be mounted on a building with BIM programs. As for problems that arose after the trial application of the prepared template, some CAD files could not be imported; also, while writing tables, the basis of calculation could not be made automatically. Regarding this, it is thought that functions of a BIM program and template need improvement.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.6
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• pp.1465-1475
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• 2015

Cheating detection models in the online games can be divided into two parts. The one is on client based model, which is designed to detect malicious programs not to be run while playing the games. The other one is server based model, which distinguishes the difference between benign users and cheaters by the server log analysis. The client based model provides various features to prevent games from cheating, For instance, Anti-reversing, memory manipulation and so on. However, being deployed and operated on the client side is a huge weak point as cheaters can analyze and bypass the detection features. That Is why the server based model is an emerging way to detect cheating users in online games. But the simple log data such as FPS's one can be hard to find validate difference between two of them. In this paper, In order to compensate for the disadvantages of the two detection model above, We use the existing game security solution log as well as the server one to bring high performance as well as detection ratio compared to the existing detection models in the market.